BALTIMORE -- Tucked into this weekend’s series between last-place teams at Oriole Park was, potentially, a first-place battle: for American League Rookie of the Year.

AL ROY remains one of this year’s most highly contested awards races with a week of baseball to play, with Orioles slugger Ryan Mountcastle and Rangers outfielder Adolis García standing out amid a crowded field that includes Astros righty Luis Garcia, Indians closer Emmanuel Clase and Rays outfielder Randy Arozarena.

• Box score

It’s a deep and talented but jumbled bunch with no clear favorite, whose winner may well come from the four-game Orioles-Rangers set that concluded in Sunday’s 7-4 O’s loss. Mountcastle and García are especially neck and neck, with similar offensive profiles and résumé points.

1B Ryan Mountcastle
Age: 24
Season stats: .258/.311/.488, 31 HRs, 84 RBIs, 4 SBs, .800 OPS, 1.1 WAR
This series: 4-for-16, HR, 3 SO

Mountcastle’s 31 homers are an Orioles rookie record and lead all MLB rookies this year. He’s hit 30 since May 7, after struggling mightily on both sides of the ball over the season’s first five weeks. That counts when analyzing Mountcastle’s season as a whole, as does the defensive issues he had in left field early on. Those are a big reason he ranks between 1 and 2 Wins Above Replacement lower than Arozarena and as much as 2.5 WAR lower than García, depending on which WAR metric is used.

Mountcastle has improved defensively since moving to first base full-time in early August, while Trey Mancini slid into more DH duties. But the glove stuff is almost certain to weigh down his ROY case, given how García (11 outs above average) is an impact defender. That said, Mountcastle clearly paces García in overall offensive production, owning a clear edge in hitting, OBP, SLG, OPS and OPS+. His biggest contribution to this series was a solo home run Thursday night.

OF Adolis García
Age: 28
Season stats: .244/.288/.459, 30 HRs, 86 RBIs, 13 SBs, .746 OPS, 3.5 WAR
This series: 5-for-18, 3 RBIs, 4 SO

Like Mountcastle, García played his way into this conversation by overcoming early season adversity. He was designated for assignment by the Rangers in February, didn’t make their Opening Day roster, was recalled in April and caught fire come May, hitting .312/.348/.633 with 11 homers in the month. García had 22 homers by the All-Star break, earning him Texas’ lone selection in the Midsummer Classic. He was the AL’s only rookie All-Star.

But García’s production never matched its May highs and began to tailspin by July; he’s hit just .216/.266/.365 since July 1, with 10 homers in 72 games. Meanwhile, Mountcastle heated up and Arozarena stayed steady, with Clase, Luis Garcia and Rays rookie Wander Franco also emerging in the ROY fray. García still leads AL rookies in RBIs, after rapping the go-ahead double off John Means in Sunday’s fifth inning. Like Mountcastle, García collected multihit games in two of the four games this weekend.